Although there is one post about steamwebhelper.exe crash. But it seems that it does no result for the issue. So I just post again with detailed info.
I see that Steam is the official application that CrossOver support , so I hope you can fix this issue ASAP. Or the there is less meanings to buy CrossOver support. Thanks!

After login and launch Steam in online mode, and with less than 1 minute, Steam itself crash because of the steamwebhelper.exe process crash. I'v try to uninstall, remove bottle, reinstall CrossOver but find nothing useful. After check in wine official site, It because of Geckto Engine used in Steam with it build-in Chromium Browser.
And Steam will check any file so it couldn't just delete or disable the steamwebhelper.exe file.

But the most interesting thing is that the CrossOver wine has use that CrossOver-patch("which inject to kernel32.dll which will launch process match "steamwebhelper.exe" with "--no-sandbox" added"), but it still crash after long time. So maybe we should try more solution.?